It has long been known that certain biologically active substances can be obtained from the glands of animals and the substance so obtained utilized in the treament of deficiencies of the human body. One such substance is the adrenocorticotropic hormone, commonly called ACTH, which for many years has been obtained from the pituitary glands of animals, particularly porcine and bovine pituitary glands.
For many years the art has eagerly awaited the discovery of more practical methods and compounds which enable the commercial synthesis of such peptides from other than natural sources. One such synthesis is set forth by Colescott, Kaiser, Bossinger and Cook in the U.S. Pat. No. 3,915,949 dated Oct. 28, 1975. Another is set forth in our co-pending application Ser. No. 672,459 filed Mar. 31, 1976.
Human adrenocorticotropic hormone (ACTH) is a polypeptide comprising 39 amino acids in a linear chain. The synthesis of peptides containing as many as 39 amino acids in its amino acid chain is a long and tedious synthesis providing many chances for error during the synthesis, and it would be a substantial advance in this art to provide a synthesis of such a peptide having a shorter amino acid chain length, especially if such desired peptide having a shorter amino acid chain length be found to have the same or greater biological activity than is contained in the natural hormone.